Many work machines have work tools with engaging portions that wear or may come unattached in the course of performing their functions. For example, an excavator or a wheel or track type loader may have a bucket with attachable teeth. The teeth may be used to break up dirt or other material when the excavator or loader is digging. In another example, a cold planer may have a rotor with attachable teeth used to break up pavement. In still other examples a landfill or soil compactor may have protrusions on the wheels used to compact trash, an earthmoving machine such as a dozer or backhoe loader may have a ripper with ripper teeth or an agricultural tractor may pull a tillage tool with chisels or other protrusions or attachments.
The engaging portions on work tools may wear or become detached from the work tool such that the work machine is unable to perform its function. If the engaging portions become detached from the work tool other problems may occur on the worksite. For example if bucket teeth from a wheel or track type loader become detached at a quarry site and an unattached tooth goes through a rock crusher, the rock crusher may be damaged and mining operations may cease for a time. If wear or detachment occurs on the protrusions of the rotor on a planer or on the chisels on a soil tillage tool, the work these tools do may become uneven and may need to be repaired.
The operator of a work machine such as an excavator or loader may be able to visually check to ensure that engaging portions of a work tool have not become detached or are not worn such that they can no longer perform their function. This may be done while work is being performed. For example, an operator may visually check a bucket whenever visible from the cab. However, there are periods of time the operator may be unable to see the engaging portions of the work tool to ensure the engaging portions have not detached. In other circumstances environmental factors such as dust may inhibit visibility. On automated work sites where the work machine is automated or operated remotely, it may be impossible for an operator to visually inspect the work tool.
Tools on some work machines may have to be visually inspected at periodic intervals with the machine in a non-working state. For example the rotor on a cold planer may have to be manually inspected at the end of each shift or scythes on a combine may need to be periodically inspected.
U.S. Pat. No. 5,743,031 discloses an apparatus for providing a signal indicative of loss or imminent loss of digging hardware normally arranged in operable association with an earth working implement. However, the apparatus for providing the signal is located on the digging apparatus itself. In some work environments this apparatus may fail. In an autonomous worksite without an operator, the signal may not be seen or recognized.
It would be preferable to have an apparatus and method that overcomes one of these and other disadvantages.